A 16-year-old surfer has died after being attacked by a shark off the NSW north coast.

The boy died at North Wall Beach at Ballina after suffering large bites to the leg and body, a Surf Life Saving NSW spokesman says.

The attack took place around 8.30am (AEST) while the boy was bodyboarding with a friend.

"Basically we know that shortly after eight o'clock this morning, two boys were surfing, or bodysurfing on bodyboards, adjacent to the North Wall at Ballina," Surf Life Saving spokesman Stephen Leahy told AAP.

"Shortly after eight o'clock one of the boys indicated that he was in trouble to his mate, his mate went over to help and found that he had been attacked.

"He brought him up on to the shore, but unfortunately the boy died due to his injuries."

Mr Leahy said all beaches in Ballina had been closed as a precaution.

Another Surf Life Saving NSW spokesman, Craig Roberts, said the boy suffered two large bites, one to the leg and one to the body.

The shark had not been spotted since, and crews were out looking for it.

"The patient came in with another gentleman and lifeguards attended the scene," Mr Roberts told ABC radio.

"As you can imagine it was quite a distressful situation.

"He was unconscious and the lifeguards and ambulance officers had some severe haemorrhage to deal with."

Mr Roberts said lifeguards performed well in the traumatic situation.

"Certainly it's one of those things that you're trained for but hopefully it never happens as well," he said.

"The lifeguards did an excellent job and worked with the ambulance and the police service, but obviously it is a traumatic experience."

The boy was surfing 50 metres out from shore at the time of the attack, he said.

Reports that a second man was attacked but survived have not been confirmed.

Mr Roberts said the beach was normally patrolled, but crews had not started patrolling for the day.

Surfers' websites say North Wall beach, just north of the Richmond River estuary, is popular, but they warn of the danger from sharks.

However Mr Roberts said it was not common for sharks to be present off North Wall beach at this time of year.

"Earlier on in the year there was a very heightened risk in the Byron (Bay) area in which we put some additional measures with jet skis and helicopters in the area," he said.

"But at this time of year it's generally not a high prone (high prone) season for the sharks."

Lifesavers will get a full report on the incident at 9.30am (AEST).

The manager of the Ballina Beach Resort, close to the site of the attack, said bull sharks had been seen recently in North Creek, near the Richmond River estuary.

"A local fisherman saw four of five of them," the manager, Sharon, told AAP.

"They are hunters," she said of the bull sharks.

The website marinebio.org says the bull shark is a massive and fearsome shark with saw-edged upper teeth, up to 3.5 metres long.

The National Geographic website says attacks attributed to great white sharks may often in fact have been attacks by bull sharks.

A spokesman for the Australian Volunteer Coastguard said it was the organisation's policy to make no comment on any incidents in which it was involved.

Police said the boy who died was from Wollongbar, between Ballina and Lismore.

His mate had raised the alarm after finding him floating unconscious in the water, they said in a statement.

He was pulled from the surf suffering heavy blood loss from severe lacerations to his upper and lower leg.

Police and NSW Ambulance personnel attended the scene, but attempts to revive the boy were unsuccessful.

MORE than three months after Wollongbar teenager Brock Curtis-Matthew tried to save his best mate from being mauled by a shark, there is little doubt in anyone's mind that he is a hero.

In recognition of his efforts, the Royal Lifesaving Society is presenting Brock with a bravery award which is to be given to him at Government House in Sydney by the Governor of NSW, Professor Marie Bashir.

Brock's mother, Victoria Matthew, told The Bulletin yesterday that her son was surprised when he heard about the award.

"He said 'Mum, it's pretty cool but I'd give it up to have Peter back'," she said. "I was really, really proud of him ... I can't even describe what he's been through.

"What he did was an incredible thing but we all miss Peter a lot.

"He's just a normal kid who did something pretty amazing."

On a Tuesday morning, April 8, Brock was surfing with fellow Alstonville High Scool Year 11 student Peter when the friend who introduced him to surfing was attacked by what is thought to have been a big bull shark.

After seeing his mate wave for help, Brock re-entered the surf and paddled through the bloodied water in a bid to rescue Peter.

Brock managed to get Peter to shore, began CPR and called for help on his mobile phone.

Despite the best efforts of emergency services, Peter was pronounced dead on the beach as a result of two large shark bites.

The attack occurred about 70m from shore, just north of the Richmond River wall at Lighthouse Beach.

Northern NSW Lifeguard co-ordinator Stephen Leahy was in charge of the beaches at the time of the incident and has been involved in several recent patrols after sightings of large sharks throughout the Ballina area over the past three months.

Mr Leahy said he was glad Brock was receiving formal recognition for his efforts.

"To witness something like that would be absolutely horrendous and obviously my heart really does go out to this young fellow who did everything possible to save his friend," he said.